This invention relates generally to disposable fabrics and fabric laminates and more particularly concerns a fabric laminate which has layers that are thermally bonded and are made from a low crystalline olefin copolymer, a low crystalline olefin terpolymer, or a low crystalline blend of olefin polymers. The fabric laminate of the present invention is softer, is stronger, is more abrasion resistant, and has reduced particle emission as compared to current SMS fabric laminates.
Nonwoven fabric laminates are useful for a wide variety of applications. Particularly, nonwoven fabric laminates are useful for wipers, towels, industrial garments, medical garments, medical drapes, sterile wrap, and the like. Fabric laminates, such as spun-bonded/melt-blown/spunbonded (SMS) fabric laminates, made of isotactic polypropylene have achieved widespread use in operating rooms for drapes, gowns, towels, sterile wraps, footcovers, and the like. Such fabric laminates are well known as shown in U.S. Pat. No. 4,041,203 assigned to Kimberly-Clark Corporation, the assignee of the present invention. For a number of years, Kimberly-Clark has manufactured and sold SMS medical fabric laminates under the marks Spunguard.RTM., Evolution.RTM., and Kimguard.RTM.. Such SMS fabric laminates have outside spun-bonded layers which are durable and an internal melt-blown barrier layer which is porous yet which inhibits the penetration of fluids and bacteria through the composite fabric laminate. The layers are thermally bonded together by spot bonding in discrete areas of the fabric.
Generally, such conventional SMS medical fabric laminates are made from layers of spun-bonded and melt-blown polypropylene. Commercially available isotactic polypropylene has a crystallinity of from 45-65% and a relatively narrow melt temperature range. While SMS fabric laminates made from commercial polypropylene exhibit satisfactory attributes in terms of tensile strength, resistance to fluid and bacteria penetration, breathability, and cost, there appears to be advantages to be gained from improving the drape, abrasion resistance, tear strength, and particle emission of the SMS fabric laminates made from polypropylene.
Conventional SMS fabric laminates made of isotactic polypropylene have not achieved widespread use as garments and protective coverings in more demanding clean rooms, particularly sterile clean rooms, and in paint rooms because of the higher requirements for such uses and such SMS fabric laminates tend to emit particles, either particles from the fabric itself or by passage of particles from the wearer to the atmosphere.